1. Field of the Invention
The present invention relates generally to cursor display methods and character input apparatuses. More particularly, the present invention relates to cursor display methods and character input apparatuses suitable for inputting a character string comprising a mixture of first-type characters having a first writing direction and second-type characters having a second writing direction opposite to the first writing direction in a character input area capable of displaying a limited number of characters.
2. Description of the Related Art
Some apparatuses having a character input function support input of a character string comprising a mixture of characters that are written in opposite directions depending on character types, such as alphabets and numerals in Arabic.
As the related art for inputting a character string of this kind, a technique for inputting a character string containing a mixture of Arabic alphabets and Latin alphabets is known as disclosed in Japanese Unexamined Patent Application Publication Nos. 60-115987, 01-205262, 05-119755, and 07-230451.
For example, in Japanese Unexamined Patent Application Publication No. 60-115987, a write-position indicator is moved from right to left to receive character input according to a writing direction of Arabic alphabets (right-to-left horizontal writing) when users input the Arabic alphabets. When the users continuously input Latin alphabets after inputting such Arabic alphabets, the input Latin alphabets are moved in the left direction in order of input with the write-position indicator being fixed, so that character input according to a writing direction of Latin alphabets (left-to-right horizontal writing) is received. In this way, input of a character string containing a mixture of Arabic alphabets and Latin Alphabets is permitted.
Since applications and devices dedicated to character input, such as word processing software and a word processor for use in personal computers (PCs), can begin a new line to display characters exceeding a limit of one input line on the next line when users input one or more lines of characters, the users can confirm a character input immediately before the latest one with their eyes.
In contrast, devices, such as in-vehicle devices, display a character input field limiting a number of displayable characters on a display unit and receive characters input in the character input field. In such devices, users may be unfortunately unable to confirm a character input immediately before the latest one.
More specifically, when a character string having a constant writing direction is input in a character input field, the input characters overflow from the character input field and are hidden in order of input as the character input progresses. Accordingly, the foregoing problem does not occur.
In contrast, the problem occurs when a character string containing a mixture of characters written in opposite directions are input in a character input field 1 as illustrated in FIG. 4.
FIG. 4 is a process chart illustrating a case of inputting an Arabic character string in the character input field 1 capable of displaying up to ten characters in order from step 1 (ST1) to step 13 (ST13). Referring to FIG. 4, Arabic characters are represented as alphanumeric characters with writing directions being adapted to Arabic ones for convenience. Latin alphabets represent characters (alphabets) in Arabic, whereas Arabic numerals represent numerals in Arabic. Additionally, illustration of steps existing between step 2 (ST2) and step 3 (ST3) is omitted in FIG. 4 for convenience. Furthermore, a blank space (i.e., a space) representing character spacing between alphabets or between an alphabet and a numeral in Arabic is included in the alphabets because the space has the same writing direction as the alphabets.
Based on such an assumption, a character string “Shinobu Doi 1945 MAY” (translated into English) constituted by 20 characters (including spaces) is to be input in the character input field 1.
As illustrated in FIG. 4, in step 1 (ST1) to step 5 (ST5), alphabets (including a space) in Arabic (hereinafter, referred to as Arabic alphabets) are input in the character input field 1 in a left direction corresponding to a writing direction of the Arabic alphabets. At this time, a cursor 2 indicating an input position of a next Arabic alphabet is also moved in the left direction from an initial display position illustrated in step 1 (ST1) as the input of Arabic alphabets progresses.
However, when the cursor 2 is moved to a left end display position of the character input field 1 as illustrated in step 3 (ST3), i.e., when the cursor 2 can be moved in the left direction no more, the display position of each of the Arabic alphabets input before the latest one is then moved in a right direction as the input of Arabic alphabets progresses with the display position of the cursor 2 being fixed as illustrated in step 4 (ST4). As a result of such movement of the display position, the Arabic alphabet “S” that has been displayed in step 3 (ST3) overflows from the character input field 1 and is hidden in step 4 (ST4).
The movement of the display position of each of the input Arabic alphabets similar to that in step 4 (ST4) is further performed twice in a row from step 4 (ST4) so that the number of times of the movement is equivalent to the number of alphabets input until an input mode is switched from the Arabic alphabets to the numerals.
After the input mode is switched from the Arabic alphabets to the numerals in step 6 (ST6), numerals are input in the right direction corresponding to a writing direction of numerals in step 6 (ST6) to step 9 (ST9). Unlike the case of inputting Arabic alphabets, the display position of the cursor 2 is fixed regardless of progression of input of numerals. Instead, a display position of each of the numerals input before the latest one is moved in the left direction.
At this time, display states of numerals in step 7 (ST7) to step 9 (ST9) may be problematic.
More specifically, a numeral “9” following a numeral “1” having been input in step 6 (ST6) is input in step 7 (ST7). At this time, since the earlier input numeral “1” overflows from the character input field 1 and is hidden as a result of moving the numeral in the left direction, there is no way for users to confirm the numeral “1”. This similarly applies to step 8 (ST8) and step 9 (ST9).
Such a problem regarding difficulty in confirming a character input immediately before the latest one has to be solved as soon as possible since the problem often induces overlooking of input mistakes, such as those in inputting an address (e.g., a house number) and in edition of a phone book or a title of a song.